1. Field of Invention
The present invention relates to a rear projection type multi-projection display.
2. Description of Related Art
Related art documents Japanese Unexamined Patent Application Publication No. 8-82854, Japanese Unexamined Patent Application Publication No. 8-94974, Japanese Unexamined Patent Application Publication No. 2001-339672, International Publication Pamphlet No. 99/31877, Japanese Unexamined Patent Application Publication No. 9-326981, Unexamined Patent Application Publication No. 2001-251651, Japanese Unexamined Patent Application Publication No. 6-178327, Japanese Unexamined Patent Application Publication No. 9-211386, U.S. Pat. No. 5,956,000, disclose a rear projection type multi-projection display in which a plurality of projector units (projection optical unit) are arranged in a horizontal direction and in a vertical direction and projection images from the plurality of projector units are projected onto a screen in a magnified scale to display one large screen image. Such a multi-projection display can display images with high definition and high brightness, as compared to other related art projectors. Thus, it is expected that the multi-projection display will have wide commercial applications in future in business fields, such as cinemas, art galleries, museums, seminar halls, assembly halls, mini-theaters, public institutes, and companies or for domestic uses, such as an amusement and a home theater.
But, in such a multi-projection display, if the projection images from the respective projector units are not connected smoothly to each other, it is impossible to match the projection images from the respective projector units to each other. Further, a boundary is remarkable, and then image quality is lowered.
For this reason, in the multi-projection display disclosed in related art documents Japanese Unexamined Patent Application Publication No. 8-82854, Japanese Unexamined Patent Application Publication No. 8-94974, in order to address and/or solve the above discussed and/or other problems, the projection images from the respective projector units are made not to overlap each other and the joint portions thereof become small.
However, in such a multi-projection display, there is a problem in that at the time of setting up, it is not easy to remove joint portions of the projection images from the respective projector units or connect the projection images without inconsistency.
For this reason, in the multi-projection display disclosed in related art documents Japanese Unexamined Patent Application Publication No. 2001-339672, International Publication Pamphlet No. 99/31877, Japanese Unexamined Patent Application Publication No. 9-326981, Unexamined Patent Application Publication No. 2001-251651, Japanese Unexamined Patent Application Publication No. 6-178327, Japanese Unexamined Patent Application Publication No. 9-211386, U.S. Pat. No. 5,956,000, in order to address and/or solve the above discussed and/or other problems, the projection images from adjacent projector units are made to overlap partially on the screen such that the projection images are smoothly connected to each other in the overlapped region.
However, in such a multi-projection display, if how the projection images from the respective projector units are displayed on the screen are not known accurately, it is impossible to connect smoothly the projection images on the screen. Thus, in the multi-projection display disclosed in related art documents Japanese Unexamined Patent Application Publication No. 2001-339672, International Publication Pamphlet No. 99/31877, Japanese Unexamined Patent Application Publication No. 9-326981, Unexamined Patent Application Publication No. 2001-251651, an image-capturing device such as a monitoring camera or a digital camera is provided at a viewer's side and the projection images (adjusting images) from the respective projector units which are displayed on the screen are captured, such that how the projection images are displayed on the screen can be accurately measured.